Thank you for your question.

The issue I am sure you can appreciate is that a lot of medications/wormers for this species are used off license. This is because the alpaca industry isn't large enough for the drug companies to rationalize the expenses associated with getting the drug licensed for them (the same happens for farmed fish, deer, and other rarer farmed species).

Therefore, we do use medications that may not have a labeled use for this species. In the case of Paramectin, it is licensed for a range of species (cattle, pigs, sheep), but is used off license in the alpaca. Alternatively, you can also worm alpacas with Ivomec, Dectomax, Panacur, Q-Drench, Fasinex (Liver Fluke) and Eprinex Pour On. All apart from the later are given by Sub Q injection.

Now the main thing to keep in mind is that we do sometimes see alpacas with drug resistant worm burdens. Therefore, when worming your alpacas you want to make sure you are having a fecal sample checked first (either submitted to the vet or direct to the lab). This way you know what type of worms are infesting your animals, whether they are resistant to your current regime, and this will guide you to making the right decisions to then treat effectively.

I hope this information is helpful.
Please do let me know if you have any further questions.
If you have no further questions, feedback is always appreciated.

All the best,

Dr. B.

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